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tab.ts10.1 kB
/** * Copyright (c) Microsoft Corporation. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import { EventEmitter } from 'events'; import * as playwright from 'playwright'; import { callOnPageNoTrace, waitForCompletion } from './tools/utils.js'; import { logUnhandledError } from './log.js'; import { ManualPromise } from './manualPromise.js'; import { ModalState } from './tools/tool.js'; import type { Context } from './context.js'; type PageEx = playwright.Page & { _snapshotForAI: () => Promise<string>; }; export const TabEvents = { modalState: 'modalState' }; export type TabEventsInterface = { [TabEvents.modalState]: [modalState: ModalState]; }; export type TabSnapshot = { url: string; title: string; ariaSnapshot: string; modalStates: ModalState[]; consoleMessages: ConsoleMessage[]; downloads: { download: playwright.Download, finished: boolean, outputFile: string }[]; }; export class Tab extends EventEmitter<TabEventsInterface> { readonly context: Context; readonly page: playwright.Page; private _lastTitle = 'about:blank'; private _consoleMessages: ConsoleMessage[] = []; private _recentConsoleMessages: ConsoleMessage[] = []; private _requests: Map<playwright.Request, playwright.Response | null> = new Map(); private _onPageClose: (tab: Tab) => void; private _modalStates: ModalState[] = []; private _downloads: { download: playwright.Download, finished: boolean, outputFile: string }[] = []; constructor(context: Context, page: playwright.Page, onPageClose: (tab: Tab) => void) { super(); this.context = context; this.page = page; this._onPageClose = onPageClose; page.on('console', event => this._handleConsoleMessage(messageToConsoleMessage(event))); page.on('pageerror', error => this._handleConsoleMessage(pageErrorToConsoleMessage(error))); page.on('request', request => this._requests.set(request, null)); page.on('response', response => this._requests.set(response.request(), response)); page.on('close', () => this._onClose()); page.on('filechooser', chooser => { this.setModalState({ type: 'fileChooser', description: 'File chooser', fileChooser: chooser, }); }); page.on('dialog', dialog => this._dialogShown(dialog)); page.on('download', download => { void this._downloadStarted(download); }); page.setDefaultNavigationTimeout(60000); page.setDefaultTimeout(5000); (page as any)[tabSymbol] = this; } static forPage(page: playwright.Page): Tab | undefined { return (page as any)[tabSymbol]; } modalStates(): ModalState[] { return this._modalStates; } setModalState(modalState: ModalState) { this._modalStates.push(modalState); this.emit(TabEvents.modalState, modalState); } clearModalState(modalState: ModalState) { this._modalStates = this._modalStates.filter(state => state !== modalState); } modalStatesMarkdown(): string[] { return renderModalStates(this.context, this.modalStates()); } private _dialogShown(dialog: playwright.Dialog) { this.setModalState({ type: 'dialog', description: `"${dialog.type()}" dialog with message "${dialog.message()}"`, dialog, }); } private async _downloadStarted(download: playwright.Download) { const entry = { download, finished: false, outputFile: await this.context.outputFile(download.suggestedFilename()) }; this._downloads.push(entry); await download.saveAs(entry.outputFile); entry.finished = true; } private _clearCollectedArtifacts() { this._consoleMessages.length = 0; this._recentConsoleMessages.length = 0; this._requests.clear(); } private _handleConsoleMessage(message: ConsoleMessage) { this._consoleMessages.push(message); this._recentConsoleMessages.push(message); } private _onClose() { this._clearCollectedArtifacts(); this._onPageClose(this); } async updateTitle() { await this._raceAgainstModalStates(async () => { this._lastTitle = await callOnPageNoTrace(this.page, page => page.title()); }); } lastTitle(): string { return this._lastTitle; } isCurrentTab(): boolean { return this === this.context.currentTab(); } async waitForLoadState(state: 'load', options?: { timeout?: number }): Promise<void> { await callOnPageNoTrace(this.page, page => page.waitForLoadState(state, options).catch(logUnhandledError)); } async navigate(url: string) { this._clearCollectedArtifacts(); const downloadEvent = callOnPageNoTrace(this.page, page => page.waitForEvent('download').catch(logUnhandledError)); try { await this.page.goto(url, { waitUntil: 'domcontentloaded' }); } catch (_e: unknown) { const e = _e as Error; const mightBeDownload = e.message.includes('net::ERR_ABORTED') // chromium || e.message.includes('Download is starting'); // firefox + webkit if (!mightBeDownload) throw e; // on chromium, the download event is fired *after* page.goto rejects, so we wait a lil bit const download = await Promise.race([ downloadEvent, new Promise(resolve => setTimeout(resolve, 3000)), ]); if (!download) throw e; // Make sure other "download" listeners are notified first. await new Promise(resolve => setTimeout(resolve, 500)); return; } // Cap load event to 5 seconds, the page is operational at this point. await this.waitForLoadState('load', { timeout: 5000 }); } consoleMessages(): ConsoleMessage[] { return this._consoleMessages; } requests(): Map<playwright.Request, playwright.Response | null> { return this._requests; } async captureSnapshot(): Promise<TabSnapshot> { let tabSnapshot: TabSnapshot | undefined; const modalStates = await this._raceAgainstModalStates(async () => { const snapshot = await (this.page as PageEx)._snapshotForAI(); tabSnapshot = { url: this.page.url(), title: await this.page.title(), ariaSnapshot: snapshot, modalStates: [], consoleMessages: [], downloads: this._downloads, }; }); if (tabSnapshot) { // Assign console message late so that we did not lose any to modal state. tabSnapshot.consoleMessages = this._recentConsoleMessages; this._recentConsoleMessages = []; } return tabSnapshot ?? { url: this.page.url(), title: '', ariaSnapshot: '', modalStates, consoleMessages: [], downloads: [], }; } private _javaScriptBlocked(): boolean { return this._modalStates.some(state => state.type === 'dialog'); } private async _raceAgainstModalStates(action: () => Promise<void>): Promise<ModalState[]> { if (this.modalStates().length) return this.modalStates(); const promise = new ManualPromise<ModalState[]>(); const listener = (modalState: ModalState) => promise.resolve([modalState]); this.once(TabEvents.modalState, listener); return await Promise.race([ action().then(() => { this.off(TabEvents.modalState, listener); return []; }), promise, ]); } async waitForCompletion(callback: () => Promise<void>) { await this._raceAgainstModalStates(() => waitForCompletion(this, callback)); } async refLocator(params: { element: string, ref: string }): Promise<playwright.Locator> { return (await this.refLocators([params]))[0]; } async refLocators(params: { element: string, ref: string }[]): Promise<playwright.Locator[]> { const snapshot = await (this.page as PageEx)._snapshotForAI(); return params.map(param => { if (!snapshot.includes(`[ref=${param.ref}]`)) throw new Error(`Ref ${param.ref} not found in the current page snapshot. Try capturing new snapshot.`); return this.page.locator(`aria-ref=${param.ref}`).describe(param.element); }); } async waitForTimeout(time: number) { if (this._javaScriptBlocked()) { await new Promise(f => setTimeout(f, time)); return; } await callOnPageNoTrace(this.page, page => { return page.evaluate(() => new Promise(f => setTimeout(f, 1000))); }); } } export type ConsoleMessage = { type: ReturnType<playwright.ConsoleMessage['type']> | undefined; text: string; toString(): string; }; function messageToConsoleMessage(message: playwright.ConsoleMessage): ConsoleMessage { return { type: message.type(), text: message.text(), toString: () => `[${message.type().toUpperCase()}] ${message.text()} @ ${message.location().url}:${message.location().lineNumber}`, }; } function pageErrorToConsoleMessage(errorOrValue: Error | any): ConsoleMessage { if (errorOrValue instanceof Error) { return { type: undefined, text: errorOrValue.message, toString: () => errorOrValue.stack || errorOrValue.message, }; } return { type: undefined, text: String(errorOrValue), toString: () => String(errorOrValue), }; } export function renderModalStates(context: Context, modalStates: ModalState[]): string[] { const result: string[] = ['### Modal state']; if (modalStates.length === 0) result.push('- There is no modal state present'); for (const state of modalStates) { const tool = context.tools.filter(tool => 'clearsModalState' in tool).find(tool => tool.clearsModalState === state.type); result.push(`- [${state.description}]: can be handled by the "${tool?.schema.name}" tool`); } return result; } const tabSymbol = Symbol('tabSymbol');

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